Hygrometric apparatus



Oct. 24, 1933. c. BURDICK HYGROMETRIC APPARATUS Filed April 25, 1952v l 4 2 2o. 5 i 1 n zu 4 rl zll i E Patented Oct. 24, 1933 UNITED .f STA-Tes VV1,93,:',o12

VHYGRQMETRICy APPARATUS Charles Laurence Burdick,V London, `England Application April 25', ,1932, serialNo. 607,359, and

in GreatBritain September 16, 1931 1g claims.` (ci. 73-24 number of cords of iibre almost or -`quiteim pervious to moisture, Vanl inner sheath apparentlyV serves as an ovular covering and is but little affected by moisture.

covering'swells, the inner cords remaining of the 'samerlength the free end of the bracts turn in- Ward and as we say the cone closes up, when the bract is drying out :the movement is'reversedthe outer covering contracts and the 4outer ends curve outward.` *y

There are many 'organic substances both vegetable and animal tissues whichabsorb moisture readily and can be made to serve'as a hygrostatic element, the advantage of lthemoisture absorbing iibre from the cone bract is itsY rigidity and its-resistance to various forms of deteriora'- tion common to most absorbent tissues. I Y

I do not confine my invention to the utilization of cone bracts, the mechanical arrangement may be used with other forms of moisturesensitive substances. l Myinvention consists inutilizing and vimproving upon this natural phenomenon in theproducl tion of hygrometrical apparatus. i 1

And further in the mechanical mounting and arrangements of parts 'whereby vhygrostatic `40 movement is amplified and made eie'ctive.

When .using the bracts themselves Iv trim them in such'a Way as to improve upon their natural effective movement.

The bracts in vclosing up not only.v moveto-.- wards the axis of the cone at their freeends but the side wings off the bracts tend to curve inward to the circumferential shape -of the closed Icone, this curvature in the cross section of the bract has a retarding action; by'trimming away the wings Vand` retaining only the central longitudinal porvtionof the bract a muchmore effective movement is obtained. Y, Y

I preferhowever to use only the moisture sensitive portionof the bract as a hygrostatic element replacing Athecords .with flexible .material .which When much moisture is present the outer may be a film of mica, celluloidz metal vor other 'flexible substance -which is preferably secured thereto by cement or painted or sprayed there on inliquid form. The hygrostatic element may be cut in strips witlif openings between to enable the air to morereadily contact .With it. -V

Two or more hygrostaticvelements may-be so mounted' and linked together as to work as -a single unit where more power is required; the coupling maybe side by side or tandem with 6 5 adjustable connections. f g

l Thev calibration of the graduated scale is such as to compensate for the changes in leverage andV the curvature of the bract. Y

In a recording hygromete'r'I Aprovide the-usual` 70 clock work mechanism with cylindrical support .for ruledsheets of paper. vSecured toa journaled Yor pivoted'shaft a long exibleV arm carrying a pen or pencil traces a'graph on the paper 'sheets as the cylinder turns; The ljournaled shaft-is rotated by means of aishorter arm securedthereto which ism'o'v'ed" by being adjustably linked with a vsuitably vmounted hyg'rostatic element or 'hygrof static elements; 'I further provide means whereby the' hygro 80 static elementsare made to yoperate valves Vcontrolling the ow of liquids or gases,'or which will operate make and break'contacts forelectrical vcurrent either in the formoffrelay appa -ratusor for direct control. f 85 Y My `invention-will b'eunderstoodffrom the 'fol- Ylowing description and ley-reference to the 'accom-L panying drawing -iniwhichi Figure 1 isa` vrepresentationof a-conifer bract. Figure 2 is as ectional View oflsa'me taken on the 9'0 .line--e-x. "Figure 3 is a partial planV viewof a .simplevr form of hygrometer. Figure 4 is aside elevationl View showing a modification of same. Figure'" is a sectional sideelevation of 'a detail of Figure 4. Figure' is 'a plan view showing 95 vanotherform of construction.4 Figureil `is'laY sectional-side elevation view` of same." Figure 8 isa side elevation. view 'of a design for ai recording hygrometer'. Figure y9 isla lpartial planview of; same;l Figure 10 shows a side elevation view 100 'y of means for" utilizing. my .inventiona for operating automatic controlsl vFigure 11 is a plan lView of. a strip which may be .used for supporting the bract. Figure 12 is a longitudinal sectional view of the` bract as attached tothe support-shown in l Figure 11. A l. 1 f

,.A'Aportion of the lupper or outside surface A v(Figel) ofV a cone'bractsuch as Iutilizefor the vdevelopment ofV my'inventionA is composed ofr a layer of fibre which absorbs moisture -quickly As the side wings are closing up there isoa. retarding inuence in the movementmofthe free: end towards the axis, to eliminatethisfI out away the wings as indicatedbythedotted lines.

D in Figures 1 and 2.

The result of this trimming is to greatly im?, prove the effective movement caused by vchanges of humidity. I prefer however to cut away all but the moisture sensitive portion of fibre in the bract and utilize Ythis in connection with -a ilexible.support;, this is illustrated in Figs. 4 and 5. The lcone bracts so prepared can :be used ,various mechanical arrangements ,for different lformsofhygrometrical apparatus. y j

The numeral 1 in thevvarious iigures represents braetssotreated,V and may also represent -any moisture absorbent substance utilized ina vvsimilar mechanical way for hygrometrical apparatus. j v Y 2 is a preferably rectangular mounting or piece made of non absorbent material (such for y.instance as hard rubber) into which the ybase of the hygrostatic element is secured by -an anhydrouscement. I have found plastic wood prepared with cellulose serviceable for this purpose.

This mounting is preferably secured in an adjustable* holder 3 which is secured in place by andv pivoted ona screw or stud 4 whileV a second screwf4' serves to retain it ina iixedposition by beingscrewed down Ona-Harige 3' of the holder 3. pg lhe mounting 2 is adjustable in the holder by .means of a. set screw-5 While a second screw 5 secures the block in its position when adjusted;

la .slot inthe kblock permitsthe movement of the blocksinrelation to the screw 5.

In the construction shown in Figs. 3, 4-and 5 the ,holder 3j is vbrought around` at its forward end 2 so .astoengage the sides of the hygrostatic element: Turning the set screw 5 will lengthen or shorten the `effective movement of the h ygrostatic elementy andthe pointer.

The gure 3 shows a simpleform of lmounting fora hygrometen indicating thernoisture in the atmosphere', the pointer '7 amplies the move= ment-lof--the'bracttand a'calibrated and numbered index, (il shows the relativeshumidity. The index may be numbered in any convenient way but preferably in percentages ofA 100 at satue ration point. Fig. 4 shows aside elevation view of theadjustable mounting but with a hygrostatic element which may be eitherva nbre from a cone bractprany other moisture absorbent material secured lto a flexible mounting as '7 which serves atthe same/time as apointer:A This is further illustrated inthe front view of Fig. 5. Fig. 4 showshow the hygrostatic element-may be vbifurcatedor cut into strips to allow for better circulation ofv the air.

vFigures 6 and 7 show a simple and enicient Y form of mounting in which a pointer 8 is mounted pivotally on apostor stud 9 and is moved by an arm 10, mounted `on the hygrostatic element, which falls in a-slot `11 `in an. extension of the pointer. y

The adjustable mounting is vsimilar to that shown in Figs. 3 and 4 except that the wing pieces 2 are removed and the movement of the block 2 by the screw 5 lengthens or shortens the leverage of the pin 10 in the slot 11.

This form of construction eliminates weights or springs and reduces rictional resistance to a minimum. I mount the hygrostatic .element on one side of a support l2 `havinganv opening 13 and the pointer on the other side, so that the circular movement of the bract and the circular rnovement of the pointer from their respective pivotalpoints will synchronize and to some extent Vequalize vthe lmovement, any discrepancies can be .metbyvariation of the calibration.

Y In this form of construction Iprovide a ventilated casingwhich may be supported on a base 14 by means of' posts or spindles 15 and be provided witha glass covering 16 for the index, a shield 17 may be provided to protect the hygrestatic element. f

- InFigures and9-a formoirecordinghygrometerisindicated The usual clock workiniechanism supporting ruledsheetsis representedby 119, .along ,spring .arm 20 supports. iazlpcniior tracing 4 a graph on the'sheetmthis arm is mountednon the journaled shaft 21-Ywhichis rotated by the hygrof static kelement adjustably secured 4tothe arm 22. 1"ig1 1 reY 10 4shows an arrangementforlutilizing my invention tol operate valvesor electricalapparatusy which are-indicated by 2S-2,3. v l Incarrying. this arrangement out itis desirable to haveA adjustable mechanism such` as is indicated )W24- 125; `*In this figured shows also howtwo or more hygrostatic elements may be coupled together to operate hygrometric apparatus. The pieces .426-26 `which mcvebacl; and forth with .the 'movement they brats yare adiustabtiy @ouf pled together in the centre by slotsandset screws falling therein. v i Y Y Y Y,

In this construction the ends oi thellyrostatic element may be slotted and theipiecesV 26 which Vfall in the slot may be pierced `to receive pins which are securedto-the hygrostatic element.

arel preferably two layers of Y cellulose. oneon each. ace oi the Strip'V 27.1 Tolialevent passible Vseparation of the celiuiosic materialfrein the iectively mounted t .f

metal, these twolayers together. through holes 291i@ strip 27. Whatclamisrf v t. In hyerometric apparatus, the .Combination with an alim @Gmigfsnefat ieastaportion Otan ovular bract ironia cone ci* a-conier treeand having one sidefcapable of: absorbingmoisture from a surrounding medium' and'v swelling-.toa greater degree than theoppositefsideg thereby causingv a flexure -ofwtlie arm'whicnvvaiiiesfwith y'different percentages ofi humidityinsaid medium, Of means for rigidly holdingl oneend'or" v the arm, leaving-the vother .end free tomov'e as -the arm ilexesf l 2. In hyg'rometricapparatus; thecombination with'an arm havingfa .eX-ible portionfcomprising at least a portion of an ovular bractfrom a cone of a'cOner'treeand capable oi flexinglto different degrees with"variations'fof-humidty vini-a surholding one end of the arm, leaving the other end free to move as the arm Ilexes.

3. In hygrometric apparatus, the combination with an arm having a flexible portion comprisingl at least a portion of anl ovular bract from a cone of a Conifer tree and capable of flexing to different degrees with variations of humidity in a surrounding gaseous. medium, of means for rigidly holding one end of the arm, leaving the other end free to move as the arm flexes, and means cooperating with the free end of said arm to` indicate the percentage of said humidity. l

4. In hygrometric apparatus, the combination with an arm having one side capable of absorbing moisture from a surroundinggaseous medium and swelling to a greater degree than the opposite side, thereby causing a flexure ofthe arm which varies with different percentages of humidity in said medium,l of means for rigidly holding one end of the arm, leaving the other end free to move as the arm exes, a pointer on said arm, a scale cooperating With said pointer, and means for adjusting the amplitude of movement of said pointer in proportion to the flexure of said arm.

5. In hygrometric apparatus, the combination with an arm comprising at least a portion of an ovular bract from a cone of a Conifer tree and having one side capable of absorbing moisture 'from a surrounding gaseous medium and swelling to a'greater degree than the opposite side, thereby causing a ilexure of the arm Whichvvaries with different percentages of humidity in said medium, of means for rigidly holding one end of the arm, leaving the other end-free to move as the arm llexes, and an instrumentality controlled by arm in accordance With lthe lexure thereof.

6. In hygrometric apparatus, the combinationv With means .movable in accordance with the per- Y and swelling to a greater degree than the oppofsite side, therebyy causing a flexure vof the arm'- centage of humidity in a surrounding gaseous medium, said `means including an arm formed from an ovular bract from a coneof a Conifer tree Yand having one side capable of vabsorbing moisture from said medium and swelling to a greater extent than the opposite side, thereby causing a flexure'thereof which varies With the moisture, and an instrumentality controlled by said means in accordance With said lexure.

7. In hygrometric apparatus, the combination.

with an arm having one side capable of absorbing moisture from a surrounding gaseous medium which variesvwith different percentages of humidity in said medium, of means for rigidly holding one end of the arm, leaving the other end free to move as the arm exes, said means being adrwhich varies with different percentages of hujustable to vary the proportionate movement of the free end of the arm as compared to the humidity of the surrounding medium.

8. In hygrometric apparatus, the combination with an arm having one side capable of absorbing moisture from a surroundingV gaseous medium and swelling to a greater degree than the oppo'- f site side, thereby causing a flexure of they arm which varies with diierent percentages of hu,` midity in said medium, of a iexible` strip rigidly mounted at one end, said arm being rmly secured to and supported by said ilexible strip, one end of the arm being freeto move as the arm exes. f Y

9. In hygrometric apparatus,'the combination with an arm having one side capable of absorbing moisture from a surrounding gaseous medium and swelling to a greater degree than the opposite side, thereby causing a ilexure of the arm midity in vsaid medium, of a ilexible strip rigidly mounted at one end and supporting said arm of absorbent material, and anhydrous material securing said arm to the flexible strip, leaving one end of said arm free to move as the arm flexes.

10. In hygrometric apparatus, thel combination with an arm having one side capable of absorbing moisture from a surrounding gaseous n medium and swelling to av greater degree than 'the opposite side, thereby causing a lexure of the arm which varies with different percentages of humidity in said medium, of a flexible strip rigidly mounted at one end and having holes therethrough, vlayers of anhydrous material on opposite faces of said strip integrally joined through said holes, said arm of absorbent material being secured to and supported by said strip by reason of its adherence to the anhydrous material.

11. In hygrometric apparatus, an arm formed from an ovular bract from the cone of a conifer tree and rigidly supported at one end, the other end of the arm being free to move in response to variations in humidity, an indicating element, means for movingsaid indicating element in proportion to the movement of the free end of the bract but through a greater distance, and a graduated scale cooperatively associated with said indicating element.

12. Inhygrometricapparatus, an indicating arm having a flexible portion formed from an ovular bract from a cone of a conifer tree, the lateral edge portions of said bract being trimmedoi lto reduce the tendency of the bract to curl 130 laterally under the influence of moisture.

CHARLES' LAURENCE BURDICK. 

